Exposed Boulders in the Aitken Mare

Boulders eroding out of the hillslope and concentrated between two hills. NAC image M143480262, image width is 700 m [NASA/GSFC/Arizona State University].

Boulder fields on the Moon are a fairly common feature. In general, large boulder fields are usually part of an ejecta deposit surrounding their parent crater or a product of gravity-driven mass wasting, where blocks on a slope are dislodged from the regolith or rock outcrops by various geologic processes (including meteorite impacts or moonquakes) and roll downhill. Since this boulder field is located at the base of a slope, it is likely a product of gravity-driven mass wasting. This field has boulders as large as 10 meters in size. Astronauts exploring Aitken crater could use boulder fields like this one, where materials from higher up have fallen to lower, more accessible elevations, to collect samples that otherwise would be very time-consuming to collect.